Fire rated grout, 5000 psi

Log Out | Topics | Search Moderators | Register | Edit Profile

Author Message Bruce Konschuh Senior Member Username: brucek Post Number: 11 Registered: 08-2014 Posted on Tuesday, November 10, 2015 - 12:14 pm:    We have a jobsite situation where we need fire rated grout (above cmu wall/below metal deck) Have you ever used this grout? Who makes it? I have checked with several major USA grout producers and found nothing. All I am finding is FP grout (with no psi on website) by Alibaba, and their site all goes thru China. I doubt they will reply to my question. Have you ever needed FR grout? George A. Everding, FCSI, CCS, CCCA, AIA Senior Member Username: geverding Post Number: 813 Registered: 11-2004 Posted on Tuesday, November 10, 2015 - 03:55 pm:    Typically individual products by themselves do not carry a fire-resistance rating. They must be part of a tested assembly. Why aren't you considering a fire-resistive joint system from the manufacturers listed in http://www.4specs.com/s/07/07-8400.html ? Ronald L. Geren, FCSI, AIA, CCS, CCCA, SCIP Senior Member Username: specman Post Number: 1363 Registered: 03-2003 Posted on Tuesday, November 10, 2015 - 10:28 pm:    Grout is cementitious, just like the rest of the CMU wall. There are no fire-rated grouts. If the full thickness is provided, then the grout has the same rating as the wall. It is similar to the exception for through penetrations. However, there is a problem using grout for the joint condition you are describing--there is no bond between the grout and the metal deck. The metal deck will move, and any movement of the deck will break whatever bond there could possibly exist, allowing the passage of smoke and hot gases through the gap. The joint should have some sealing capability like a standard joint sealant, whether the joint is static or dynamic. UL has a several head-of-wall assemblies designed for use with metal decks and CMU (usually as an option in lieu of CIP concrete walls) for gaps up to 6 inches, all of which are considered dynamic. However, the CMU, per UL, "shall bear the UL or ULc Certification Mark," which is problematic, since there are few manufacturers that have CMU with the UL Certification Mark. Personally, I think requiring the mark for CMU is a UL racket (they do not require a certification mark for concrete materials in a concrete wall). Any CMU complying with ASTM C 90 should be acceptable. If there is any weakness in a fire-resistance-rated CMU wall, it will be in the mortar joints and not the CMU--and the mortar joint materials require no UL Certification Mark. To overcome this obstacle, negotiations with the AHJ in the form of a code modification may be necessary by either requesting the use of non-UL-certified CMU or submitting an engineering judgement by the manufacturer of the joint materials indicating non-UL-certified materials are acceptable. Ron Geren, FCSI, AIA, CCS, CCCA, SCIP www.specsandcodes.com Bruce Konschuh Senior Member Username: brucek Post Number: 12 Registered: 08-2014 Posted on Thursday, November 12, 2015 - 05:21 pm:    Thanks for your thoughts re this issue. We went the route of "Grout is cementitious, just like the rest of the CMU wall. There are no fire-rated grouts." There are a few FR mortars, but the psi was too low. Actually, the FR grout from Alibaba does meet the required 5000 psi, but I doubt the AHJ would have approved it. Mark Gilligan SE, Senior Member Username: mark_gilligan Post Number: 770 Registered: 10-2007 Posted on Thursday, November 12, 2015 - 09:55 pm:    I concur with Ronald regarding UL certification of CMU although I would be less polite. The IBC provides a fire rating for CMU walls. I suggest you use this rating. Dave Metzger Senior Member Username: davemetzger Post Number: 613 Registered: 07-2001 Posted on Thursday, November 12, 2015 - 11:18 pm:    Alibaba is a distributor, not a manufacturer (sort of like Grainger but on a much larger, more wide-ranging scale) John Bunzick, CCS, CCCA, LEED AP Senior Member Username: bunzick Post Number: 1654 Registered: 03-2002 Posted on Sunday, November 15, 2015 - 06:02 pm:    Actually, Alibaba is more like Amazon, serving as an ecommerce portal for many companies selling products. They have several sites, including Taobao and Tmall. They are part-owned by Yahoo, and the founder, Jack Ma, is China's richest citizen, worth about $25 billion.